| 摘要 |
PROBLEM TO BE SOLVED: To provide a light-emitting device which can sufficiently radiate heat of a wavelength conversion part, and effectively prevent decrease in light emission output of the wavelength conversion part.SOLUTION: A light-emitting device includes: a solid light source 11 which emits, as excitation light, light of a predetermined wavelength among wavelength regions from ultraviolet light to visible light; a plate-like wavelength conversion part 12 having a phosphor which is excited by the excitation light from the solid light source 11 and emits fluorescent light; and radiation holding parts 13 which hold the wavelength conversion part 12. When a direction of one end surface 12c and the other end surface 12d of the wavelength conversion part 12 which contact the radiation holding parts 13 is determined as X, and a direction of the one end surface 12c and the other end surface 12d vertical to the direction X is determined as Y, length of an optical axis direction Z of plate-like flat parts 12a, 12b of the wavelength conversion part 12 and length of the direction X of the one end surface 12c and the other end surface 12d contacting the radiation holding parts 13 are longer than length of the direction Y of the one end surface 12c and the other end surface 12d. |
